Device for indicating whether a clock is running



y 1935- 0 B. F. MULDOON 2,002,905

DEVICE FOR INDICATING WHETHER A CLOCK IS RUNNING Filed July 1, 1932 Patented May 28, 1935 UNITED STATES PATENT OFFICE Bernard F. Muldoon,

signor to Henry 1 Claim. This invention relates to a device for enabling an observer who looks at a clock to ascertain the time and recognize instantly whether or not the clock is running. The invention is especially useful in connection with electric clocks or clocks which are noiseless or have no pendulums or other parts which move at a visible speed. This invention enables clocks of this character to be used Without requiring the observer to wait in order to ascertain whether or not such clocks are running.

Devices heretofore used for this purpose have not proved to be entirely satisfactory. For example, a rapidly moving hand compared to the movement of the minute hand of such a clock has been mounted concentric with the mounting of the minute and hour hand so that the observer can, without waiting a long time, see if the clock is running. Such a hand is objectionable as it is often mistaken for the minute or hour hand, especially when one merely glances at the clock to ascertain the time. Another device that has been used for this purpose is to have an opening in the face of the clock through which a disc with segments of different colors can be observed, this disc being driven comparatively rapidly by a portion of the clock mechanism. An objection to this device is that it cannot be seen very well or from considerable distances, especially when the clock is not in a well-lighted location.

By the present invention an object or member which reflects li ht is attached to a rapidly moving part of the clock mechanism and is of such a character that it can be seen a long distance and indicates instantly Whether or not the clock is running. The light reflecting object or member is preferably located in front of the face of the clock and is attached to a relatively rapid moving part of the clock mechanism, and also preferably has a plurality of light reflecting surfaces in planes at angles to each other so that a large number of rays of light will be reflected therefrom in different positions and these rays will be moved across the line of sight of observers in diiferent positions, thus attracting attention to the movement of the object or memher.

The invention will be understood from the description in connection with the accompanying drawing in which Fig. l is a front view of attached and Fig. 2 is a side elevation of a suificient portion of the clock mechanism to show how the indicating device may be attached and rotated.

Mountain View, N. J., as- Hyman, Brooklyn, N. Y.

Application July 1, 1932,

Serial No. 620,413

In the drawing reference character I indicates a clock casing that is provided with the usual face 2, hour hand 3, and minute hand 4, the hands being journalled on concentric axes in the well known way, as indicated at 5.

A rapidly moving shaft 6 of the clock mechanism such, for example, as the shaft to which a second hand may be attached, extends through an opening in the face 2 and carries a lightrefiecting member 7.

of reflected rays projected in different directions. For example, the light-reflecting member 7 may be a jewel that has facets thereon, or it may be made of any appropriate material with the light-reflecting surfaces at angles to each other. The light reflecting surfaces may be surfaces of the member or object itself, or the light reflecting surfaces may be provided by coating the surfaces of the material with different sorts of well-known coating materials which provide surfaces that reflect light.

It has also been found advantageous to mount the light-reflecting member I eccentric to the shaft 6, as indicated at 8 in Fig. 2, as this has been found to enhance the visibility of the rotating object and make it more ascertain by a mere glance at it whether o not it is stationary.

The light reflecting object or member '1 may be mounted upon any moving part of the mechanism which moves sufficiently rapidly to stopped. In the illustrative embodiment of the invention the field 9 of an electric motor of a well-known type is indicated. The motor has poles l0 and an armature H so that the motor will run in synchronism with the frequency of the alternating current that is used. The armature II is mounted on the shaft I 2 which carries a gear [3 meshing with a gear [4 on the shaft 1 so that the shaft 7 is driven at a comparatively high speed due to the very high speed of the armature l I.

It is to be understood that while the lightreilecting member has been shown and described as being immediately in front of the clock face, it may be located in other positions in proximity to the clock, but should be so located that the observer can see it Without difficulty when he looks at the clock to ascertain the time.

impression of a lively movement that attracts tests with this device in actual use it has been found that it instantly indicates to the observer several hundred feet away whether the clock is running, whereas with other devices used for this purpose the observer must be very much nearer and must make an appreciably greater effort to recognize Whether the clock is running. When a faceted jewel or other object having light-reflecting surfaces at angles to each other 0 is used the scintillating appearance gives the attention and can be seen even when the sight is directed specifically to the hands of the clock.

I claim: In a clock, a rotating shaft having an end projecting in front of the face of said clock, 7

and a faceted member attached thereto and eccentric thereof. I

BERNARD F. MULDOON. 

